ABSTRACT
Objective: To establish a high-throughput platform for drug discovery targeting receptor binding domain (RBD) of SARS-CoV-2, a surface display system was designed and constructed to deliver functional RBD to the surface of Pichia pastoris. Methods: Four anchor molecules were fused to RBD, and then were transformed into Pichia pastoris by using electroporation. The surface display efficiency of RBD was measured using flow cytometry, and the affinity of RBD binding to the ACE2 receptor was further determined. Results: RBD-Sed1p system exhibited the highest surface display efficiency of 70%. The binding affinity to ACE2 of RBD displayed on the cellular surface (KD=30.42 nmol/L) was close to that of RBD in solution (KD=16.00 nmol/L). Conclusion: A surface display system of RBD was successfully developed in Pichia pastoris, which can be used for high-throughput screening and evaluation of anti-COVID-19 drugs. © 2022, China Biotechnology Press. All rights reserved.
ABSTRACT
The outbreak of the COVID-19 has increased the demand for point-of-care testing ( POCT), and as the most indispensable tools for human beings at present, smartphones have great application potential in POCT. Smartphone-based POCT has the following unique advantages: ( 1) easy to operate and without the need for professional training;( 2) shorter wait times and quicker test results;( 3) low fabrication cost and convenient to use in limited-resource areas. Therefore, smartphone-based POCT is rapidly emerging as a potential alternative to traditional laboratory testing. Herein, we perform a comprehensive review of recent progress and applications of smartphone-based sensors in POCT for the past three years, which uses the tested objects ( body fluids, volatile organic compounds, vital signs) by POCT as the basis for classification, and combines with the current mainstream sensing strategies, including colorimetric, fluorescent, electrochemical technology, piezoelectric, pyroelectric, ultrasonic and photoelectric sensor, etc. We evaluate the performance and development potential of these sensors, in addition, the emerging technologies used in POCT are introduced, such as nanotechnology, flexible electronic devices, microfluidic technology, biodegradable technology, self- powered technology, multichannel detection and so on. Finally, current problems are summarized and the future development of the smartphone-based POCT is discussed.
ABSTRACT
Background: The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes the disease COVID-19, has caused a pandemic that has rapidly affected the whole world and caused a significant threat to public health. The aim of this study was to investigate and analyze the social and occupational effects of the COVID-19 pandemic on patients with multiple sclerosis (MS) in three different countries: China, Spain, and Cuba. Methods: A cross-sectional survey was designed to assess the social and occupational effects of the COVID-19 pandemic in MS patients in these three countries, using a 25-item anonymous online questionnaire, structured into three sections. Quantitative data are expressed as mean (standard deviation), and quantitative data as absolute frequency and percentage. Results: A total of 361 participants responded to the questionnaire: 194 from China, 104 from Spain, and 63 from Cuba. We found no cases of COVID-19 among Chinese patients with MS, and few cases in Spain and Cuba. Respondents reported different levels of impact on relationships with friends, family, and colleagues, and patients in all three countries described increased use of digital or social media platforms. Spanish patients reported a significantly less negative impact than those in Cuba and China. Mental and cognitive effects were similar in all three countries, although China seemed to have a better situation. We also found that the time spent exercising decreased at specific points during the pandemic, but with few changes in dietary habits. Patients reported little or no change in their means of transport in all three countries. Most patients in all three countries reported little or no physical deterioration, especially in Chinese patients (82.47%), compared to the Spanish (70.20%) and Cuban respondents (73.02%). In general, patients from all three countries demonstrated confidence in overcoming the COVID-19 pandemic, although to a lesser extent among Spanish respondents. Conclusions: During the pandemic, family support was more effective in China than in Cuba and Spain. Neither COVID-19 infections nor the number of MS relapses increased significantly during lockdown in any of the three countries. Regarding their economic situation, Spanish MS patients reported a significantly less severe negative impact than those in Cuba and China. Patients from all three countries used digital or social media platforms more frequently, probably to maintain personal relationships. Chinese and Cuban respondents were more confident of the control of the pandemic than the Spanish, who were more pessimistic. © 2021
ABSTRACT
Objective: To analyze the epidemiological and clinical characteristics, and imaging features of patients with COVID-19 in Henan Province People's Hospital. Methods: The epidemiology, clinical symptoms, laboratory and radiologic data of 49 patients with COVID-19 infection admitted to the department of infectious disease in our hospital from January 23, 2020 to February 22, 2020 were retrospectively analyzed. All analyses were performed with SPSS software, version 22.0. Results: A total of 49 patients with COVID-19 were enrolled, of which 28 were ordinary, 16 were severe, and 5 were critical in disease severity. The average ages of the 3 groups were (46±19) , (60±16) and (68±20) years, with statistical differences (P=0.015). Common symptoms at the onset were fever (41 patients), dry cough (35 patients), and fatigue (21 patients). Epidemiological investigations found that 31 (63%) patients had direct or indirect contact with confirmed cases, and 14 cases were family clustered. Laboratory test results showed that the lymphocyte counts progressively decreased [0.85 (0.5-1.6) ×10(9)/L,0.51 (0.4-0.9) ×10(9)/L and 0.43 (0.47-0.61) ×10(9)/L, respectively], while LDH [162 (145.1-203.5) U/L,265 (195.3-288.4) U/L and 387 (312.3-415.5) U/L, respectively] and D-dimer [0.15 (0.09-0.40) mg/L,0.4 (0.2-0.6) mg/L and 0.9 (0.5-1.4) mg/L, respectively] were significantly increased (P<0.05), in all the 3 groups. The levels of IL-6 [(43.2±15.4) µg/L, (78.5±31.2) µg/L and (132.4±47.9) µg/L, respectively] and IL-10 [(3.5±3.2) µg/L, (7.6±6.4) µg/L and (9.4±7.2) µg/L respectively] increased significantly with disease severity. Pulmonary imaging of ordinary patients mainly showed unilateral or bilateral multiple infiltrates, while severe and critically ill patients showed diffuse exudation and consolidation of both lungs, and a few patients showed signs of "white lungs". Conclusions: Patients with COVID-19 has a definite history of contact with diagnosed patients, and has family aggregation. The clinical symptoms were mainly fever and dry cough. Laboratory results showed that lymphocyte count, LDH, D-dimer, interleukin-6 and interleukin-10 levels had a significant correlation with the severity of the disease, which could be used as markers for disease progression and prognosis. Pulmonary imaging showed unilateral or bilateral ground glass infiltration. In severe and critically ill patients, diffuse infiltration and consolidation or even "white lung" were present.